1× 4GB DDR4 Laptop Memory RAM PC4 2400MHz 260-pin - Samsung M471A5244CB0-CRC. Note this advert is for a single ram, if you are interested in the pair, you need to buy 2. Get in touch for the postage combination if you're buying two. Taken out from my HP Elitebook 820 G4. It was on my laptop for the first month and I didn't use it much. So pretty much like brand new.
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